Field
The disclosure generally relates to an optical touch film, a display device including the same, and a manufacturing method thereof.
Discussion
A display device, such as a liquid crystal display (LCD) and an organic light emitting diode (OLED) display, typically includes a pixel electrode and an electro-optical active layer. For example, an OLED display may include an organic emission layer as the electro-optical active layer, and an LCD may include a liquid crystal layer as the electro-optical active layer. The pixel electrode can be connected to a switching element, such as a thin film transistor, to be applied with a data signal, and the electro-optical active layer can convert the data signal into an optical signal to display an image.
A display device may also include a sensing function for enabling interactions with a user in addition to a function of displaying an image. The sensing function is a function that may determine whether an object approaches or contacts a screen of the display device, and can provide contact information about a contact position, etc., by detecting a change in pressure, charge, acoustics, or light that are applied to a screen when a user approaches or contacts the screen with a finger, a touch pen, etc., to input characters, draw pictures, and/or otherwise interact with the display device. The display device may receive an image signal to display an image based on the contact information.
A sensing function may be realized through a sensor. The sensor may be classified according to various methods, such as a resistive type, a capacitive type, an electro-magnetic (EM) type, an acoustic type, an optical type, etc. Among these methods, a capacitive type of sensor typically includes a plurality of touch electrodes to transmit a detection signal. A touch electrode may form a sensing capacitor alone or with an adjacent touch electrode. If a conductor, such as a finger, approaches or comes in contact with the sensor (or the screen of the display device), a change in capacitance is generated by the detection capacitor or a change in a charged amount, thereby enabling a contact existence and a contact position to be determined.
A plurality of touch electrodes may be disposed at a touch sensing region of a display device in which the contact can be sensed, and may be connected to a plurality of signal transmitting wires transmitting a detection signal. A sensor may be formed inside the display device (e.g., an in-cell type sensor), or may be formed directly on an outside surface of the display device (e.g., an on-cell type sensor). As another example, a separate touch sensor unit (or module) may be attached to the display device (e.g., an add-on cell type sensor). A touch-sensitive flexible display device usually includes a film with a sensor, and the film is typically attached to a display panel of the flexible display device in the add-on cell type manner.
The above information disclosed in this section is only for enhancement of an understanding of the background of the inventive concepts, and, therefore, it may contain information that does not form prior art already known to a person of ordinary skill in the art.